This: usage notes
Imprecise use of this, and its plural these, in formal writing has become common. This pattern seems to reflect inappropriate pronoun use, as well as confusion among these words’ several uses as pronouns, adjectives, and adverbs. We use all these forms idiomatically in speech, generally without substantial vagueness. Avoid such idiomatic expression in formal writing.
This and these work effectively when the antecedent is clear and specific. Use of this to refer to the preceding paragraph, or to a complex idea obscures meaning. Do not make your reader labor unnecessarily to comprehend your meaning.
Not: Attendance at movies declined precipitously after the mass distribution of video tape players, but this is changing in the digital age.
Rather: Attendance at movies declined precipitously after the mass distribution of video tape players, but theatre attendance has been increasing in the digital age.
Or: Attendance at movies declined precipitously after the mass distribution of video tape players, but this decline is changing in the digital age.
Of course, there are many examples of fine literature that violate guidelines for effective style, such as Thomas Paine’s opening sentence in his pamphlet The Crisis (1776), “These are the times that try men’s souls.” Nevertheless, Paine would have lost no content had he written, “These times try men’s souls.” (JS)
this (ðis), pron. and adj., pl. these (ðez); adv. pron. 1. (used to indicate a person, thing, idea, or event as present, near, just mentioned, or by way of emphasis): This is my coat. 2. (used to indicate one of two or more persons, things, etc., referring to the one nearer in place, time, or thought; opposed to that): This is Liza and that is Amy. 3. (used to indicate one of two or more persons, things, etc., implying a contrast; opposed to that ) : Do this, not that. 4. what is about to follow: Watch this!; adj. 5. (used to indicate a person, place, thing, or degree as present, near, or characteristic): This book is mine. 6. (used to indicate the nearer in time, place, or thought of two persons, things, etc.; opposed to that ). 7. (used to imply mere contradistinction; opposed to that). 8. (used in place of an indefinite article for emphasis): I heard this funny noise.; adv. 9. (used with adjectives and adverbs of quantity or extent) to the extent indicated: this far. —Idiom 10. with this, hereupon: With this, he wept. [bef. 900; (pron., adj.) ME] (Simon & Schuster, Webster's College Dictionary, 1999).
